PAT_B_1063_C++(20分)

#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
int main()
{
    int n;
    scanf("%d",&n);
    double max=0;
    for(int i=0;i<n;i++){
        int a,b;
        scanf("%d %d",&a,&b);
        double m=sqrt((double)(a*a)+(double)(b*b));
        if(m>max){
            max=m;
        }
    }
    printf("%.2lf\n",max);
    return 0;
}